For an image forming apparatus having a cassette which accommodates one or more sheets on which images are formed, an operation for feeding sheets to the cassette to refill the cassette needs to be performed, when the cassette has no more sheets. According to a conventional image forming apparatus in the related art, a user withdraws the cassette from an apparatus body, and sets one or more sheets in the withdrawn cassette in order to fill the empty cassette. However, the sheet feeding operation performed by the user is troublesome. For example, in order to withdraw the cassette, the user, who may be initially holding the sheets to be fed with both hands, has to withdraw the cassette. To do so, the user may have to temporarily place the held sheets somewhere beforehand in order to free the user's hands so that cassette may be withdrawn.